In many well environments, gases can build up and interfere with the production of desired liquids. Hydrocarbon based liquids, for example, can be produced by electric submersible pumping systems that are deployed within a wellbore. These types of pumping systems utilize centrifugal pumps having multiple stages that rely on impellers to move the produced liquid. However, the presence of sufficient gas in the liquid can lead to a buildup of gas on the suction surface of impeller blades, causing premature stalling of the individual stages. Furthermore, the relatively high gas-to-liquid ratio fluids can create large gas structures along the exterior of the pumping system that ultimately interfere with the production of well fluid.
Furthermore, system modeling has indicated that operation of an electric submersible pumping system in a wellbore can create multiple (meta) stable states that have substantially differing production rates. It is likely that flow transients, e.g. flow instabilities or perturbations, trigger the transition between these high and low productivity states.
Attempts have been made to prevent premature stall and to dampen flow oscillations so as to enhance the stability of system performance. For example, impeller blade angles have been reduced and holes have been drilled through impeller blades in multiple pump stages of submersible pumps. However, such approaches limit the performance and efficiency of the pumping system.